J Mater Sci Technol ›› 2011, Vol. 27 ›› Issue (9): 802-808.

• Thin Film and Coatings • Previous Articles     Next Articles

AC Conductivity and Dielectric Relaxation Behavior of Sol-gel BaxSr1-xTiO3 Thin Films

Ala'eddin A. Saif, P. Poopalan   

  1. Microfabrication Cleanroom, School of Microelectronic Engineering, University Malaysia Perlis (UniMAP), Kuala Perlis, 02000 Perlis, Malaysia
  • Received:2010-08-31 Revised:2010-12-19 Online:2011-09-28 Published:2011-09-28
  • Contact: Ala'eddin A.Saif

Abstract: BaxSr1-xTiO3 sol-gel thin films with x=0.5, 0.7 and 0.8 have been fabricated as Al/BST/Pt capacitor. The AC conductivity and dielectric properties over a frequency rang of 10 Hz and 1 MHz have been studied in order to explore the ion dynamics and relaxation mechanisms in the films. The frequency dependent conductivity plots show three regions of conduction processes. Dielectric results show that ε' at low frequencies increases as Sr content decreases, whereas at high frequencies, it shows opposite variation, which is attributed to the dipole dynamics. The electric modulus plots reveal the relaxation peaks which are not observed in the ε'' plots and the contribution of the grains, grain boundaries and electrode to the relaxation mechanisms.

Key words: Barium strontium titanate (BST) thin film, AC conductivity, Dielectric relaxation, Electric modulus